Piston ring



April 1935. J. c. LEONARD 1,999,466

PISTON RING Filed A ril 25, 19:54 2 Shets-Sheet 1 April 30, 1935..

PISTON RING Filed April 25, 1954 2 Sheets-$heet 2 J. (Z LEONARD I 1,999,466

Pa en ed Apr- UNITED STATES PATENT OFFICE PISTON RING John 0. Leonard, Oakland, Calif.

Application April 25, 1934, Serial No. 722,293 8 Claims. (01. 309-29) My invention relates to improvements in piston forced, against the resistance of its own tension, rings of the class generally used on the pistons into place over diametrically opposed portions of of internal combustion motors, steam engines, the master ring member, in the direction indipumps, compressors, and the like, although also cated by the arrow 1.

useful for other purposes; and'one of the ob- Referring to the drawings in detail, throughout 5 jects of the invention is the provision of a piston which like reference characters designate like ring that will cure certain and obvious imperparts: 1 fections inherent in the piston rings at present The letterA designates the master ring member, in common use; which is preferably formed of cast iron and. em-

A further object is the provision of a piston ring bodies a minor section I rectangular in cross sec- 10 that is quick and efiectivein expansion aswell as tion and a major section 2 T-shaped in cross in contraction to meet the, requirements of the section whereby is formed an outwardly projecting present day high-speed and high-compression rib 3 and a pair of like rabbets 4 on opposed sides motors; of said rib.

A still further object is to provide a ring hav- The minor section I comprises approximately 15 ing like upper and lower surfaces whereby it may I 44 degrees of the circumference of the master ring be readily reversed relative to the piston; member, although the proportion of said section Astill further object is the provision of amaster relative to that of the major portion or section ring members cooperable .with a pair of identical 2, may be varied to suit conditions met with in complemental ring members, the latter being apthe various motor designs. 20 plicable by springing and slipping them into their A gap 5, severing the rim at the mid portion of respective rabbets formed in the master ring section 2, permits of necessary expansion and member after the latters installation on the piscontra'ctionof the master ring member. ton. Two like complemental ring members B, which Iobtainthe above-mentioned, and other objects are preferably formed of steel wire of relatively 25 and purposes that will become apparent ,as the dense material than the material comprising the description proceds, by providing a master ring cast iron master ring element A, are disposed in member embodying a major ring portion T- the rabbets 4 and preferably spring-press with shaped in cross section whereby is'formed a censuiiicient pressure against the convex surface of tral rib and a pair of rabbets one on each side of the master ring member to be normally carried 30 said rib, and a minor ring portion substantially thereby. rectangular in cross section; the said rabbets In the application of my present improved pisbeing provided with a pair of coacting completon ring to the groove of a piston, the master ring mental ring members of like design. 7 member A isfirst applied, which may be done in In the accompanying drawingsthe usual manner of applying rings to motor 35 Figure 1 is a plan view of the present improved pistons, after which application of the master piston ring, assembled; ring member, the two complemental ring mem- Figure 2 is a P Vi f the master r g members B are applied, each, separately, by inserting i its free ends in one of the rabbets 4, as shown in figures 3 and 3a are plan Views of the Fig. 8, and then pushing it forward in the rab- 4 plerpenta'l members; bet between the rib- 3 and the wall of the cylinder figure an g w of groove (not shown), in the direction indicated by lgure is an e g8 mew 0 8 master nng the arrow i, causing it to expand resiliently regg g 6 is a sectional View on M e of sistingly into the position shown in Fig. 9, and

Fig thence moving it further forward in the same f 7 is an enlarged View in perspective of a direction, while diametrically contracting, until portion f the master ring member; it slips into its normal position in the rabbet as Figure 8 is a plan view of the master ring ele-. best ShQWn in Figs- 1 and ment and-one of th commemental ring member, The inner line curvature of the complemental 50 the latter in its initial position for application to ring members B is intended to be slight more the master ring member; and acute than the convex surface of the rabbet in Figure 9 is a plan view of the master ring memwhich it is ad p d to a thereby causing it, her and one of the complemental ring members, W S0 seated, to b a d bind against said the latter being expanded diametrically by being vex surface with sumcient force to prevent its im- 55 thus disposed in the cylinder, the normal tendency of the master ring member is to expand and to press against the cylinder walls, and the said master ring member having greater cross sectionali dimensions than. the complemental ring members B, as well as 'being formed of denser and harder material than the material'forming the latter, it likewise has greater expansive force, causing it to overcome any contractile resistance the complemental ring members may exert thereagainst, and to cause said complemental ring members to expand therewith to properly press against the cylinder'wall notwithstanding their normal tendency to contract diametrically, wherebyv said complemental ring members are caused to cooperate with the master ring member in forming a proper seal between the wall of the cylinder and the. piston.

I claim:

1. Ina piston ring of the character described,

a master ring member havinga portion substantially rectangular in cross section and having another portion T-shaped in cross section, said first named portion, comprising an arc of a circle of between and degrees in extent. 2. In a piston ring of the "character described, a master ring member having a portion substantially rectangular in cross section and having another portion T-shaped in cross section, and a pair of complemental ring members disposed in bearing association with said last named portion, said complemental ring members being substantially crescentshaped.

3. In a piston ring of the character described, a master ring member having a minor portion substantially rectangular in 'cross section and havingra major portion IT-shaped in cross section, and a pair of crescent-shaped complemental ring members disposed in association with said T-shaped portion, whereby the latter portion is.

' a master ring member having a minor portion substantially rectangular in cross section and having a major portion T-shaped in cross section, and a pair of coacting crescent-shaped complemental ring members in association with said a major portion. the space between the inner sur f face of each' of said complemental'ring members, adjacent the free ends thereof, being normally less than the maximum diameter of said master ring member.

. 5. In a piston ring of the character described, a master ring member embodying a minor por tion substantially rectangular in cross section, and a major portion T-shaped in cross section whereby is formed an outwardly projecting rib and a rabbet on each side of said rib, and a pair of identical crescent-shaped complemental ring members disposed in said rabbets, the free end portions of said complemental ring members spring-pressing against'the convex walls of said rabbets whereby said complemental ring members are held in bearing engagement with opposed portions of said master ring member.

6. In a piston ring of the character described, a; master ring member embpdying a minor portion substantially rectangular in cross section and a major portion substantially T-shaped in cross section thereby providing an outwardly projectshaped in cross section, said T--shaped portion providing anoutwardly projecting rib anda rah-- bet on each side of said rib, and a pair of complemental ring member's disposed in said rabbets, the free ends of said complemental ring. members being operatively engageable with said rectangular portion for limiting certain longitudinal movement of said complemental ring members in the plane of their curvature relative to said master ring member.

.8. In a piston ring of the character described. a master ring member embodying a minor portion substantially rectangular in cross section and a major portion substantially T-shaped in cross section, said T-shaped portion providing an outwardly projecting"rib and'a rabbet on each side thereof, and a complemental ring member disposed in each of said rabbets, said complemental ring membersbeing relatively movable in the plane of their curvature, the free ends of said complemental ring members being adapted to engage said rectangular portion for limiting certain longitudinal movement of said complemental ring members in either direction about the axis or said masterring'member relative to the latter.

JOHN C. LEONARD 

